This invention relates to a workstation, apparatus and methods for the high-throughput synthesis, screening and/or characterization of combinatorial libraries. The invention includes a workstation, an array, a covered array, and an apparatus comprising the array, as well as methods for using and making these. These methods include the use of an array, which may be transferred between a series of different synthesis, screening, or characterization stations.
The use of combinatorial techniques to generate libraries of chemical and/or biological compounds is known in the art. Once these libraries have been generated, it is necessary to screen or characterize the compounds to determine if the desired properties are present, i.e. physical, chemical and/or biological properties, for example. However, most techniques developed for screening and characterization of combinatorial libraries are sequential, involve sample preparation or sample transfer steps, and are generally labor-intensive, time-consuming and expensive for large libraries or arrays of several compounds.
What is needed in the art are apparatus and methods for high-throughput multiple parallel synthesis, followed by high-throughput screening and characterization of individual components in arrays or combinatorial libraries. In addition, these techniques should preferably be easily adapted to microscale techniques. Further, these techniques and apparatuses should be adaptable not only to areas where combinatorial chemistry is commonly used, such as pharmaceutical, biotechnology, and agrochemical research, but also to a broad range of disciplines, including catalysis and polymer chemistry.
Methods and apparatus for screening diverse arrays of materials in parallel using infrared imaging techniques are described in WO 98/15813. WO 97/32208 describes a catalyst testing process and apparatus, which includes methods and apparatus for parallel testing of catalysts. Despite these developments, there remains a need for techniques for the synthesis, screening, and characterization of individual compounds of a combinatorial library in the same array in a highly parallel fashion, without requiring the transfer of compounds from the array for analysis. This invention answers this need.
Moreover, the analysis of physical properties such as viscosity have yet to be adapted to combinatorial arrays, in a highly parallel manner and as applied to a broad range of compounds. WO 98/15501 describes systems and methods for characterization of materials and combinatorial libraries with mechanical oscillators. However, it does not appear that these methods would be generally adaptable to compounds other than liquids. U.S. Pat. No. 5,710,374 describes an electronic viscometer, and U.S. Pat. No. 5,889,351 describes a device for measuring viscosity and a device for measuring characteristics of fluid, but neither of these is designed or adapted for analysis of compounds other than liquids, or for combinatorial analysis of arrays. Work on electrostrictive principles has been reported in R. E. Pelrine et al., Proceedings of the 10th Annual IEEE International Workshop on Microelectrode Mechanical Systems, Nagoya, Japan, pp. 238-243. However, this work has not been adapted for combinatorial chemistry. Also recently reported in WO 98/15501 is a combinatorial method to measure the molecular weight and molecular weight distribution of polystyrene in situ, using an array of vibrating reeds. However, this vibrating reed technique measures only the viscosity of the polymer mixture in solution. Accordingly, what is needed in the art are combinatorial techniques for measuring the viscosity of samples in arrays, and techniques for measuring viscosity which are not restricted to liquids. This invention answers this need.
Also needed in the art are combinatorial techniques for measuring the comonomer content of compounds. Although WO 97/37953 describes mass-based encoding and qualitative analysis of combinatorial libraries, these techniques are used primarily as a means for encoding, and are not adapted to quantitative analysis of the comonomer content of compounds or incorporation of a reagent, for compounds synthesized in combinatorial libraries. Polymer composition has not been investigated using radiography. Cracks and formations in polymer films have been investigated by diffusing a radiolabeled gas or liquid into a preformed polymer and scanning the sample using radiography. (See e.g., Figge, K. et al., Deut. lebensm-Rundsch 66(9):281-9 (1970), Bellazzini, R. et al., Nucl. Instrum. Methods Phys. Res. Sect. A A251(1):196-8 (1986), Mysak, F. et al., Izotoptechnika, 14(1-2):27-28 (1971), Bekman, I. N., et al. Radiokhimiya 28(2):222-229 (1986), and Kocbynka, D. et al., Radioisotopy 8(6):860-1 (1967)). Radiography has been used extensively for the rapid screening of biological samples. Yet, radiography has not been generally extended for the analysis of a variety of compounds. For example, polymer compositions (e.g., comonomer content) have never been investigated using radiography. Therefore, what is needed in the art is a technique for screening and characterization of combinatorial libraries that provides a qualitative and/or quantitative determination of comonomer content or incorporation of a reagent. This invention answers this need.
There have also been some developments in the characterization and screening of combinatorial libraries. For example, in-situ resonance enhanced multiphoton ionization (REMPI) spectroscopy has been demonstrated for rapid characterization of gaseous products produced by arrays of dehydrogenation catalysts. (S. M. Senkan, et al., Angew. Chem. Intl. Ed., 38:791 (1999)). In addition, techniques for the parallel screening of heterogeneous oxidation catalysts have been described in WO 98/15813 and WO 97/32208. Techniques for simultaneously measuring catalyst activity and the molecular weight of the forming polymer in an array of 48 reactors has also been reported. (See U.S. Pat. No. 5,762,881 (1998)). Although these techniques have increased throughput in many cases, the relatively large reactor volume of the arrays and the capital investment to purchase new reactor blocks restricts the use of these arrays.
Although methods and apparatus for surface diagnostics have been reported in U.S. Pat. No. 4,733,073, these methods have not yet been adapted to the analysis of combinatorial libraries. U.S. Pat. No. 5,959,297 teaches mass spectrometers and methods for rapid screening of different materials. However, these methods appear to be slow and are not run under realistic process conditions. Therefore, what is needed in the art are mass spectrometry techniques which are run under realistic process conditions. Similarly, although method and apparatus for modulated differential analysis has been described in U.S. Pat. No. 5,224,775 and methods and apparatus for spatially resolved modulated differential analysis have been described in U.S. Pat. No. 5,248,199 these methods have not yet been adapted to the microscale or to combinatorial techniques. Methods for mass spectrometry, adapted to combinatorial chemistry are needed. This invention answers this need.
Adapting these combinatorial chemistry techniques to the microscale is particularly a challenge in fields such as catalysis and polymer chemistry. Catalytic olefin polymerization, for example, is sensitive to small variations in conditions and has rarely been attempted using microscale combinatorial techniques. However, if microscale combinatorial techniques could be adapted for use in these fields, this would significantly facilitate research and development, with the advantages of lower reagent costs, higher throughput, and greater efficiency.
There have been some attempts to adapt combinatorial synthesis techniques to the field of catalysis and polymer chemistry. In one case, combinatorial hydrothermal syntheses for zeolites was reported. (See D. E. Akporiaye, et al., Angew. Chem. Intl. Ed., 37:609 (1998) and J. Klein, et al., Angew. Chem. Intl. Ed., 37:3369 (1998)). However, high-throughput methods for screening and characterizing the components of the library, in the same apparatus used for the synthesis have not been described.
The combinatorial synthesis and analysis of supported and unsupported organometallic compounds and catalysts (e.g. homogeneous catalysts) has been described in WO 98/03521. In one embodiment, the substrate has an array of materials fixed thereon and the detector has X-Y motion. In another embodiment, the detector is fixed and the substrate having an array of materials thereon has R-xcex8 motion. WO 98/15969 describes mass spectrometry and methods for rapid screening of libraries of different materials. However, for large combinatorial libraries, these sequential methods can be time-consuming and expensive. In addition, these methods.are not adapted such that the compounds could be synthesized in the same array used for analysis.
What is needed are techniques which could efficiently screen and characterize libraries of polymers in a high-throughput manner. Further, these methods for screening and characterizing the polymer should preferably be adaptable to the microscale. This invention answers this need.
Accordingly, what is needed is a workstation, apparatus, and methods adapted for any combination of combinatorial synthesis, screening and/or characterization steps, without requiring excessive sample handling or transfer of components from the array between these steps. Preferably these methods will be non-consumptive, highly parallel, generally adaptable to the microscale, and generally applicable in many fields. Preferably, these techniques could be automated, such that the same array is moved between several different stations or analytical instruments. This invention answers this need.
This invention relates to a workstation, apparatus, and methods for high-throughput synthesis, screening and characterization of individual compounds in combinatorial libraries. The invention also relates to an array having a plurality of wells, an apparatus comprising the array, or an automated workstation where the same array is moved between several different analytical instruments or stations, as well as methods for using these.
In one embodiment, the invention relates to an array which may be directly transferred between synthesis, screening, and characterization stations or instruments, preferably without requiring sample handling, sample preparation, or sample transfer steps. Preferably, the synthesis, screening, and characterization steps are carried out in a highly parallel manner, such that more than one compound is synthesized, screened and/or characterized at a time. Moreover, the array is also easily adapted to the microscale for several different types of reactions, including catalytic and polymerization reactions.
In an embodiment of the invention, the array has thermal channels, which may be metalized or doped, and are used to provide control of the thermal conditions within a well. The thermal channels may be present in a variety of arrangements. For example, at least one thermal channel may be aligned parallel to at least one of the rows or columns. In some embodiments, there may be two thermal channels on either side of the row of wells. It is also possible to provide different temperature ranges to different thermal channels. In another arrangement for the thermal channels, the wells are arranged in an array of rows and columns and the thermal channels define a checkerboard pattern around the wells; this arrangement is often used to provide isothermal conditions for synthesis or analysis.
In another embodiment of the invention, the bottom of the wells comprises a membrane layer, which is flexible, thermally conductive, or gas-permeable. The membrane will typically comprise at least one material selected from the group consisting of: silicon, doped silicon, silicon dioxide, doped silicon dioxide, steel, sapphire, a glass material, a ceramic material, or a plastic material. In a preferred embodiment, the membrane will comprise at least one material selected from silicon, doped silicon, steel, silicon nitride and silicon oxynitride. In a particularly preferred embodiment, the membrane will comprise at least one material selected from silicon and doped silicon. When doped silicon is used, the dopant is preferably boron, phosphorus, or arsenic. The membrane layer will typically be of a substantially uniform thickness. For instance, the membrane may have a thickness from about 100 nm to about 1 xcexcm, from about 1 xcexcm to about 50 xcexcm, or from about 1 xcexcm to about 20 xcexcm.
In a another embodiment of the invention, the array comprises thermal channels and the wells in the array further comprise a membrane forming a layer at the bottom of the well. In this embodiment, the features of the thermal channels and the membrane layer are as described in other embodiments, and any additional features of any other embodiment, either taken alone, or in combination may be incorporated.
Further, this invention applies generally to both arrays of compounds or mixtures of compounds in combinatorial libraries. There may be individual compounds in each well, or mixtures of compounds. Moreover, the invention is not limited to fields such as pharmaceutical research, biotechnology, and agrochemistry, but may also be applied to a number of fields, including but not limited to, fields involving polymers, catalysts, superconductors, zeolites, magnetic materials, phosphors, thermoelectric materials, and high and low dielectric materials.
This invention relates to apparatus and methods for the high-throughput synthesis, screening and/or characterization of combinatorial libraries. In some embodiments, the invention relates to an array, a covered array, and/or an apparatus comprising the array. These apparatus are designed such that the array can be transferred between synthesis, screening and/or characterization operations, without requiring sample transfer from the array, or excessive sample preparation steps. In a preferred embodiment, the synthesis, screening, and/or characterization is carried out in a highly parallel fashion, where more than one compound or component of the library is synthesized, screened, and/or characterized at the same time. In a preferred embodiment, the invention is adapted to the microscale.
The invention also relates to a covered array, comprising the array and an array cover, as well as an apparatus comprising the array, which comprises the array, an array cover and a stage. The array, array cover, and the stage may be interchanged or modified as needed for a particular application.
The invention also relates to a variety of methods for a combinatorial chemistry process, screening, and characterizing. In the combinatorial chemistry process, combinatorial libraries are synthesized in the array. After synthesis, the array may then be transferred to a number of screening and/or characterization stations. However, the invention is not limited to compounds synthesized in the array. For example, methods of the invention are not limited only to compounds synthesized in the array. Alternatively, compounds that have been previously synthesized or purchased, may be placed in the array for high-throughput screening and/or characterization.
The invention relates to a number of methods for the screening and/or characterization of compounds in a combinatorial library in the array. In one embodiment, the invention relates to a process for thermal imaging, where the heat generated in each well of the array is monitored in real time with a camera. This method may be used to screen and identify promising wells for further study and/or characterization. In another embodiment, the invention relates to a process for the parallel differential scanning calorimetry, where reactions may be run under isothermal conditions to obtain reaction kinetics data and thermodynamic data, for example. The invention also relates to methods for measuring the viscosity, stiffness and heat deflection temperature of compounds of the array by using an electrostatic interaction to induce vibrations of the silicon membrane, which are correlated to various physical properties of the compounds in each well. The invention also relates to methods for determining the incorporation of a labeled reagent into a product of the array by digital autoradiography; this method is particularly useful for techniques such as determining the co-monomer content of a polymer.
The invention relates to a workstation, comprising at least one stage to support at least one array, and at least one unit or analytical instrument. The array comprises a substrate having a plurality of wells. The unit or analytical instrument may be selected from any synthetic or analytical instrument, and is used for synthesis, screening and/or characterization of combinatorial libraries.
The workstation may further comprise means for transferring the array from a first analytical instrument to one or more other analytical instruments. The workstation may also comprise means for transferring the array, such as a robotic hand. In an embodiment of the invention, the workstation is automated. For instance, the array is bar-coded, and/or the workstation further comprises array hotels.
Any of the embodiments of the invention may be used either alone or taken in various combinations. Additional objects and advantages of the invention are discussed in the detailed description that follows, and will be obvious from that description, or may be learned by practice of the invention. It is to be understood that both this summary and the following detailed description are exemplary and explanatory only and are not intended to restrict the invention.